1. Field of the Invention
The invention concerns a compressor, particularly for use in an air conditioning system in a motor vehicle.
2. Prior Art
Compressors of the type referred to here are well known. They are characterized by a pump unit enclosed in a housing. The housing is made up of several parts. As these are high pressure devices, to assure a reliable pressure seal, the parts of the housing are fitted with flanges and are screwed or bolted together. Because of the flanges, which stick out, conventional compressors are relatively large. It is also necessary to carefully select the material which comprises the flanges and screws or bolts to assure that the compressor functions safely under all conditions.
Generally, well-known air conditioning compressors in motor vehicles are designed as axial piston pump devices and are comprised of one or more pistons moving in a cylinder block, which draw the medium which is to be compressed from a suction chamber to a compression chamber. In order to do this the pistons reciprocate, this movement being effected by a swash plate rotating about an axis, in conjunction with a take-up plate, which is attached to the pistons. The take-up plate is fixed against rotation, typically by a thrust bearing attached to the compressor housing.
In such conventional compressors, the support for the take-up plate is quite complex, and the mechanism contains numerous different parts. In addition, the take-up plate is often weakened by the support mechanism.
Known compressors of this type also have the disadvantage that the attachment of the drive-shaft to the swash plate is achieved by means of pins or grouting. This means that a relatively large construction area is required.
In compressors of the type referred to here, one part of the housing serves as a cover for another part of the housing.
This lies on a specially designed sealing surface or sometimes on the cylinder block or on a valve plate of the device to draw the pressurized material. The cover has at least two sealing bridges, which are pointed towards the sealing surface and seal at least two pressure chambers from one another and from the environment. It has been found that it is not always possible to achieve the same level of surface compression at both sealing bridges, and that pressure can be lost if the component is elastically mishappen. i.e. if the cover portion becomes mishappen.